Chip package and fabrication method thereof

ABSTRACT

A chip package includes a substrate having a pad region, a device region, and a remained scribe region located at a periphery of the substrate; a signal and an EMI ground pads disposed on the pad region; a first and a second openings penetrating into the substrate to expose the signal and the EMI ground pads, respectively; a first and a second conducting layers located in the first and the second openings and electrically connecting the signal and the EMI ground pads, respectively, wherein the first conducting layer and the signal pad are separated from a periphery of the remained scribe region, and wherein a portion of the second conducting layer and/or the EMI ground pad extend(s) to a periphery of the remained scribe region; and a third conducting layer surrounding the periphery of the remained scribe region to electrically connect the second conducting layer and/or the EMI ground pad.

CROSS REFERENCE

This application is a Divisional of U.S. application Ser. No.12/896,277, filed on Oct. 1, 2010, now U.S. Pat. No. 8,399,963, whichclaims the benefit of U.S. Provisional Application No. 61/247,668, filedon Oct. 1, 2009, the entirety of which are incorporated by referenceherein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a chip package, and in particularrelates to a chip package having a shield structure for EMI resistanceand manufacturing method thereof.

2. Description of the Related Art

As chip packages and signal transmission continue become thinner andlighter, electromagnetic interference (EMI) problems for the chippackages become worst. With the size of chip packages shrinking, forminga satisfactory EMI shield structure is now more difficult. For example,the positions of the EMI ground pads may often be limited ormanufacturing costs may be too expensive.

Therefore, a novel chip package and manufacturing method thereof isdesired to overcome the problems mentioned above.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention provides a chip package,comprising: a semiconductor substrate having at least a contact padregion, at least a device region, and a remained scribe region locatedat a periphery of the semiconductor substrate; a signal contact padstructure and an EMI ground pad structure disposed on the contact padregion; a first opening and a second opening penetrating into thesemiconductor substrate to expose the signal contact pad structure andthe EMI ground pad structure, respectively; a first conducting layer anda second conducting layer located in the first opening and the secondopening and electrically connected to the signal contact pad structureand the EMI ground pad structure, respectively, wherein the firstconducting layer and the signal contact pad structure are separated froma periphery of the remained scribe region by an interval, and wherein aportion of the second conducting layer and/or a portion of the EMIground pad structure extend(s) to a periphery of the remained scriberegion; and a third conducting layer surrounding the periphery of theremained scribe region to electrically connect to the second conductinglayer and/or the EMI ground pad structure.

In addition, an embodiment of the present invention provides a methodfor forming a chip package, comprising: providing a semiconductorsubstrate having a plurality of die regions and predetermined scriberegions, wherein each of the die regions comprise at least a contact padregion and at least a device region, and the predetermined scriberegions surround the die regions, wherein the predetermined scriberegion comprises an actual scribe region, and a remained scribe regionis between the predetermined scribe region and the actual scribe region;forming a signal contact pad structure and an EMI ground pad structureon the contact pad region; forming a first opening and a second openingin the die region to expose the signal contact pad structure and the EMIground pad structure; forming a first conducting layer and a secondconducting layer in the first opening and the second opening toelectrically contact with the signal contact pad structure and the EMIground pad structure, respectively, wherein the first conducting layerand the signal contact pad structure are separated from a periphery ofthe predetermined scribe region or the remained scribe region by aninterval, and the second conducting layer and/or a portion of the EMIpad structure at least extend(s) to an interface between the remainedscribe region and the actual scribe region; and dicing the semiconductorsubstrate along the actual scribe region to separate a plurality of chippackages, wherein the second conducting layer and/or a portion of theEMI ground pad structure extend(s) to a periphery of the remained scriberegion.

A detailed description is given in the following embodiments withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading thesubsequent detailed description and examples with references made to theaccompanying drawings, wherein:

FIGS. 1A-1H are cross-sectional views showing the steps of forming achip package according to an embodiment of the present invention;

FIGS. 2A-2C are cross-sectional views showing the steps of forming achip package according to an embodiment of the present invention;

FIGS. 3A-3C are cross-sectional views showing the steps of forming achip package according to an embodiment of the present invention; and

FIGS. 4A-4B are cross-sectional views showing the steps of forming achip package according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description is of the best-contemplated mode of carryingout the invention. This description is made for the purpose ofillustrating the general principles of the invention and should not betaken in a limiting sense. The scope of the invention is best determinedby reference to the appended claims.

It is understood, that the following disclosure provides many differentembodiments, or examples, for implementing different features of theinvention. Specific examples of components and arrangements aredescribed below to simplify the present disclosure. These are, ofcourse, merely examples and are not intended to be limiting. Inaddition, the present disclosure may repeat reference numbers and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.Furthermore, descriptions of a first layer “on,” “overlying,” (and likedescriptions) a second layer include embodiments where the first andsecond layers are in direct contact and those where one or more layersare interposing the first and second layers.

A CMOS image sensor device package is taken as an example. However, aMEMS chip package or other semiconductor chips may also be suitable forimplementation. That is, it should be appreciated that the chip packageof the embodiments of the invention may be applied to active or passivedevices, or electronic components with digital or analog circuits, suchas opto electronic devices, micro electro mechanical systems (MEMS),micro fluidic systems, and physical sensors for detecting heat, light,or pressure. Particularly, a wafer scale package (WSP) process may beapplied to package semiconductor chips, such as image sensor devices,light-emitting diodes (LEDs), solar cells, RF circuits, accelerators,gyroscopes, micro actuators, surface acoustic wave devices, pressuresensors, ink printer heads, or power IC.

The wafer scale package process mentioned above mainly means that afterthe package process is accomplished during the wafer stage, the waferwith chips is cut to obtain separate independent packages. However, in aspecific embodiment, separate independent chips may be redistributedoverlying a supporting wafer and then be packaged, which may also bereferred to as a wafer scale package process. In addition, the abovementioned wafer scale package process may also be adapted to form chippackages of multi-layer integrated circuit devices by stacking aplurality of wafers having integrated circuits.

Referring to FIGS. 1A-1H, cross-sectional views showing the steps forforming a chip package according to an embodiment of the invention areshown. As shown in FIG. 1A, a semiconductor substrate 300 is firstprovided, which is typically a semiconductor wafer (such as a siliconwafer) or a silicon substrate. In addition, a plurality of deviceregions 100A is defined in the semiconductor substrate which issurrounded by peripheral contact pad regions 100B. The device regions100A and the peripheral contact pad regions 100B together form a portionof the die regions.

As shown in FIG. 1B, a semiconductor device 302 is then formed in thedevice region 100A, such as an image sensor or a MEMS device. Aninterlayer dielectric layer 303 (IMD) covers the semiconductor substrate300 and the semiconductor device 302, which may be low-k insulatingmaterial, such as a porous oxide layer. Then, a plurality of contact padstructures is formed in the interlayer dielectric layer 303 of theperipheral contact pad regions 100B. In this embodiment, the formedcontact pad structures comprise a signal contact pad structure 304 a andan EMI ground pad structure 304 b. The contact pad structures mentionedabove may preferably be formed of copper (Cu), aluminum (Al), or othersuitable metal material.

In addition, the semiconductor substrate 300 may be covered with a chippassivation layer 306. Meanwhile, in order to electrically connect tothe elements in the chip to outside circuits, the chip passivation layer306 may be defined in advance to form a plurality of openings 306 hexposing the contact pad structures.

Then, as shown in FIG. 1C, a package layer 500 is provided for bondingwith the semiconductor substrate, and only the contact pad structures304 a and 304 b are shown in the semiconductor substrate 300 forsimplicity. The package layer 500 may be, for example, a transparentsubstrate such as a glass substrate, another blank silicon wafer,another silicon substrate, or another wafer including integratedcircuits. In one embodiment, a spacer layer 310 is used to separate thepackage layer 500 and the semiconductor substrate 300, wherein a cavity316 surrounds the spacer layer 310. The spacer layer 310 may be asealant resin or a photosensitive insulating material, such as epoxy,solder mask, and so on. In addition, the spacer layer 310 may be formedon the semiconductor substrate 300, and then bonded with the packagelayer 500 using an adhesion layer. Meanwhile, the spacer layer 310 mayalso be formed on the package layer 500, and then bonded with anopposing semiconductor substrate 300 using an adhesion layer.

Referring to FIG. 1D, the package layer 500 may be used as a carriersubstrate, and an etching process such as an anisotropic etching processmay be performed to a back surface 300 a of the semiconductor substrate300 to remove a portion of the semiconductor substrate 300. Openings 300ha and 300 hb exposing the signal contact pad structure 304 a and theEMI ground pad structure 304 b would be formed, respectively.

FIG. 1E shows a cross-sectional view of the semiconductor substrate 300with a larger area, which includes a portion of the die region shown inFIG. 1D and a scribe region nearby and another die region. The scriberegion typically includes a predetermined scribe region SC2, andreference number “SC1” represents a region which will be actually cut bya dicing blade. In this embodiment, the spacer layer 310 overlying theEMI ground pad structure 304 b traverses the predetermined scribe regionand extends overlying the EMI ground pad structure 304 b of anotherperipheral contact pad region. However, the spacer layer 310 overlyingthe die regions mentioned above may also be two separate discontinuousstructures. In addition, when referring to FIG. 1E, one skilled in theart should understand that the size and the position of the scriberegion SC1 may be different depending on type, size, and dicing processvariations, and FIG. 1E is not limiting. The predetermined scribe regionSC2 is usually wider than the actual scribe region SC1 such that anremained scribe region SC3 is left after the actual dicing process toprevent the elements in the semiconductor substrate 300 from beingdamaged during dicing.

As shown in FIG. 1E, an insulating layer 320 exposing the signal contactpad structure 304 a and the EMI ground pad structure 304 b is optionallyformed in the openings 300 ha and 300 hb. For example, a silicon oxidelayer may be simultaneously formed in the openings 300 ha and 300 hb byusing a thermal oxidation process or a plasma enhanced chemical vapordeposition process. The silicon oxide layer may extend to the backsurface 300 a of the semiconductor substrate 300. Then, the insulatinglayer overlying bottom portions of the openings 300 ha and 300 hb areremoved by, for example, an etching process, to expose the signalcontact pad structure 304 a and the EMI ground pad structure 304 b. Inthis embodiment, the insulating layer 320 in the openings 300 ha and 300hb is formed simultaneously. In addition, the insulating layer 320 inthe openings 300 ha and 300 hb may be formed separately depending onrequirements. For example, a thick insulating layer may be formed in theopening 300 hb exposing the EMI ground pad structure 304 b.

Then, as shown in FIG. 1F, a first conducting layer 330 a and a secondconducting layer 330 b are formed in the opening 300 ha and opening 300hb, respectively. In this embodiment, if needed, the first conductinglayer may be a redistribution layer. Thus, the redistribution layer maynot only be formed to overly a sidewall of the opening 300 ha but alsobe formed to extend and overly the lower surface 300 a of thesemiconductor substrate 300. However, it should be noted that the firstconducting layer 330 a does not electrically contact with the secondconducting layer 330 b. In addition, the first conducting layer 330 a isat least separated from a periphery of the actual scribe region SC1 byan interval 335. It is preferable that the first conducting layer 330 ais separated from a periphery of the predetermined scribe region SC2 byan interval.

Further, in this embodiment, the second conducting layer 330 b may alsobe used as a redistribution layer. Thus, the redistribution layer maynot only be formed to overly a sidewall of the opening 300 hb but alsobe formed to extend and overly the lower surface 300 a of thesemiconductor substrate 300. In addition, the second conducting layer330 b further extends across the scribe region SC2 and to another dieregion. As shown in FIG. 1F, the second conducting layer extending intothe predetermined scribe region is denoted as reference number “330 c”for clarity, which at least extends to an interface between the remainedscribe region SC3 and the actual scribe region SC1. For example, in thisembodiment, the second conducting layer 330 b further links with thesecond conducting layer 330 b in another die region through theconducting layer 330 c. However, it should be appreciated thatembodiments of the invention are not limited thereto. In anotherembodiment, the second conducting layer 330 b may extend across thescribe region SC2 and reach another die region, but does notelectrically contact with the second conducting layer 330 b in anotherdie region. Alternatively, in another embodiment, the second conductinglayer 330 b may also extend merely to the actual scribe region SC1, andnot further extend to another nearby die region.

The method for forming the first conducting layer 330 a and the secondconducting layer 330 b may include a physical vapor deposition, chemicalvapor deposition, electroplating, or electroless plating process and thematerial thereof may be a metal material such as copper, aluminum, gold,or combinations thereof. The material of the first conducting layer 330a and the second conducting layer 330 b may include a conducting oxidesuch as indium tin oxide (ITO), indium zinc oxide (IZO), or combinationsthereof. In one embodiment, a conducting layer is conformally formedoverlying the entire semiconductor substrate 300. Then, the conductinglayer is patterned to has the distribution of the conducting layer shownin FIG. 1F. Although the conducting layer is conformally formedoverlying the sidewalls of the openings 300 ha and 300 hb, theconducting layer may also substantially fill the openings 300 ha and 300hb completely in another embodiment. In addition, in this embodiment,the first conducting layer 330 a and the second conducting layer 330 bin the openings 300 ha and 300 hb are separated from the semiconductorsubstrate 300 by the same insulating layer 320.

Referring to FIG. 1G, a method for forming a passivation layer 340 isshown. In an embodiment of the invention, the passivation layer 340 may,for example, be a solder mask. A solder mask material may be appliedoverlying the back surface 300 a of the semiconductor substrate to formthe passivation layer 340. Then, the passivation layer 340 is patternedto form a plurality of opening of the terminal contacts exposing aportion of the first conducting layer 330 a and the second conductinglayer 330 b. Then, an under bump metallurgy (UBM) (not shown) and aconducting bump 350 are formed at the opening of the terminal contact.For example, the UMP may be formed of a conducting material such as ametal or metal alloy, and may be a nickel, silver, aluminum, cooper, oralloy layer, or a doped polysilicon, single crystal silicon, orconducting glass layer. In addition, refractory metal material such astitanium, molybdenum, chromium, or titanium-tungsten layer may be usedalone or combined with other metal layers. In a specific embodiment, anickel/gold layer may be partially or entirely formed overlying asurface of the metal layer. Wherein, the conducting bumps 350 may beelectrically connected to the signal contact pad structure 304 a and theEMI ground pad structure 304 b through the first conducting layer 330 aand the second conducting layer 330 b, respectively. In an embodiment ofthe invention, the conducting bump 350 connecting the signal contact padstructure 304 a is used to transmit I/O signals of elements (not shownin FIG. 1G and reference may be made to the devices 302 shown in FIG.1B). The conducting bump 350 connecting the EMI ground pad structure 304b is used as a ground.

Then, the semiconductor substrate 300 is diced along the scribe regionSC1 (i.e., scribe line) in the peripheral contact pad regions to form aplurality of separate chip packages. FIG. 1H shows a cross-sectionalview of one of the chip packages. After being diced, both sides of thechip package include the remained scribe region SC3 between thepredetermined scribe region SC2 and the actual scribe region SC1.

As shown in FIG. 1H, in this embodiment, after a plurality of separatechip packages are formed, a third conducting layer 330 d surrounding aperiphery of the remained scribe region SC3 may be optionally formed.Because the first conducting layer 330 a and the signal contact padstructure 304 a are separated from the periphery of the actual scriberegion SC1 or the remained scribe region SC3 by an interval, the formedthird conducting layer 330 d does not electrically contact with thefirst conducting layer 330 a and the signal contact pad structure 304 ato affect signal transmission.

In addition, because the conducting layer 330 c traverses across thescribe region SC1 or further extends to a nearby die region, after thechip packages are separated from each other by the dicing process, aportion of the conducting layer 330 c is exposed on a surface of theperiphery of the remained scribe region SC3. Thus, after the thirdconducting layer 330 d is formed, the third conducting layer 330 d mayelectrically connect to the EMI ground pad structure 304 b through theexposed conducting layer 330 c and the second conducting layer 330 b.The third conducting layer 330 d surrounding the chip package provideselectromagnetic interference shielding effects.

In one embodiment, the third conducting layer 330 d may be applied tocompletely overly the periphery of the chip package. The thirdconducting layer 330 d may be formed by any conducting layer formingprocess and/or patterning process. For example, the third conductinglayer 330 d may be formed overlying the periphery (i.e., the peripheryof the remained scribe region SC3) of the chip package by anelectroplating process. Alternatively, in another embodiment, theconducting bump 350 and the opening of the terminal contact in thepassivation layer 340 may not be formed in advance. The processesrelating to the conducting bump 350 may be performed after the thirdconducting layer 330 d is formed.

FIGS. 2A-2C are cross-sectional views showing the steps for forming achip package according to another embodiment of the present invention,wherein same or similar reference numbers are used to designate same orsimilar elements. In addition, materials or forming methods of the sameor similar elements which are the same as or similar to the embodimentshown in FIG. 1 are not illustrated again.

As shown in FIG. 2A, this embodiment is similar to the structure shownin FIG. 1E. The main difference is that the dicing process of the chippackage of the embodiment shown in FIG. 2 is performed stepwise. Asshown in FIG. 2A, before the insulating layer 320 is formed, a recess400 is formed in the scribe region SC2 of the semiconductor substrate300. For example, a dicing blade may be used to cut a portion of thescribe region SC2 from the back surface 300 a of the semiconductorsubstrate 300 to form a cavity 400 with an inclined outline. In anotherembodiment, the recess may extend into the spacer layer 310 to apredetermined depth. That is, the surface layer of the spacer layer 310may serve as a barrier layer of the dicing blade. In addition, thedeeper the cut of the dicing blade, the nearer the subsequently formedconducting layer 330 c is to the spacer layer. Thus, the conductinglayer 330 c may completely cover the sidewall of the die. Then, theinsulating layer 320 may be formed in the first opening 330 ha, thesecond opening 300 hb, and the recess 400 simultaneously. The insulatinglayer 320 is patterned to expose the signal contact pad structure 304 aand the EMI ground pad structure 304 b as shown in FIG. 2A. Theperiphery of the remained scribe region SC3 is surrounded by theinsulating layer 320.

Then, as shown in FIG. 2B, similar to the embodiment shown in FIG. 1,the first conducting layer 330 a, the second conducting layer 330 b, andthe conducting layer 330 c, extending across the scribe region and tothe nearby die region, are respectively formed in the first opening 330ha, the second opening 330 hb, and the recess 400. In this embodiment,the conducting layer 330 c is conformally formed on the recess 400 andhas an inclined outline. The conducting layer 330 c electricallycontacts with the second conducting layers 330 b at the two adjacent dieregions, respectively. However, as mentioned above, the conducting layer330 c at least needs to be extended to the interface between theremained scribe region SC3 and the actual scribe region SC1. It is notnecessary that the conducting layer 330 c links with the conductinglayer 330 c in another die region. Then, a patterned passivation layer340 may be formed to protect the chip package and define opening of theterminal contacts.

As shown in FIG. 2C, the conducting bumps 350 are formed in thepreviously defined opening of the terminal contacts. The semiconductorsubstrate 300 is diced along the scribe line (i.e., the scribe regionSC1) to form a plurality of separate chip packages. In this embodiment,the conducting layer 330 c, extended to overly the inclined outline ofthe remained scribe region SC3, surrounds the periphery of the remainedscribe region SC3, which may be used as the third conducting layer toprovide an EMI shield. In this embodiment, the third conducting layer(i.e., the conducting layer 330 c) and the second conducting layer 330 bare formed during the same process without the need for additionalprocesses. The third conducting layer (i.e., the conducting layer 330 c)surrounds the insulating layer 320 overlying the periphery of theremained scribe region SC3.

FIGS. 3A-3C are cross-sectional views showing the steps for forming achip package according to another embodiment of the present invention,wherein same or similar reference numbers are used to designate same orsimilar elements. In addition, materials or forming methods of the sameor similar elements which are the same as or similar to the embodimentshown in FIG. 2 are not illustrated again.

The structure shown in FIG. 3A is similar to that shown in FIG. 2A. Themain difference is that the recess 400 with an inclined outline is notformed in this embodiment. A recess 502 having a substantially verticaloutline is formed instead. For example, a portion of the semiconductorsubstrate 300 may be removed from the back surface 300 a of thesemiconductor substrate 300 by a dry etching process. Thus, forming arecess 502 having a vertical outline. In one embodiment, the recess 502,the first opening 300 ha, and the second opening 300 hb may besimultaneously formed during the same etching process. Alternatively, inanother embodiment, the recess 502, the first opening 300 ha, and thesecond opening 300 hb may be formed separately depending on differentconditions. Then, the insulating layer 320 may be simultaneously formedin the first opening 300 ha, the second opening 300 hb, and the recess502. The insulating layer 320 is patterned to expose the signal contactpad structure 304 a and the EMI ground pad structure 304 b as shown inFIG. 3A.

Then, as shown in FIG. 3B, similar to the embodiment shown in FIG. 2,the first conducting layer 330 a, the second conducting layer 330 b, andthe conducting layer 330 c, extending across the scribe region and tothe nearby die region, are respectively formed in the first opening 330ha, the second opening 330 hb, and the recess 502. In this embodiment,the conducting layer 330 c is conformally formed on the recess 502 andhas a vertical outline. The conducting layer 330 c electrically contactswith the second conducting layers 330 b in two adjacent die regions,respectively. However, in another embodiment, the conducting layer 330 cat least needs to be extended to the interface between the remainedscribe region SC3 and the actual scribe region SC1. For example, theconducting layer 330 c merely extends to the actual scribe region SC1.Then, a patterned passivation layer 340 may be formed to protect thechip package and define the opening of the terminal contacts.

As shown in FIG. 3C, the conducting bumps 350 are formed in thepreviously defined opening of the terminal contacts. The semiconductorsubstrate 300 is diced along the scribe line (i.e., the scribe regionSC1) to form a plurality of separate chip packages. In this embodiment,the remained scribe region SC3 has an L-shaped outline. In addition, theconducting layer 330 c, extending to overly the L-shaped outline of theremained scribe region SC3, surrounds the periphery of the remainedscribe region SC3, which may be used as the third conducting layer toprovide a shield to the EMI. In this embodiment, the third conductinglayer (i.e., the conducting layer 330 c) and the second conducting layer330 b are formed during the same process without the need for additionalprocesses.

FIGS. 4A-4B are cross-sectional views showing the steps for forming achip package according to another embodiment of the present invention,wherein same or similar reference numbers are used to designate same orsimilar elements. In addition, materials or forming methods of some sameor similar elements are same as or similar to the embodiment shown inFIG. 1 and thus are not illustrated repeatedly.

The structure shown in FIG. 4A is similar to that shown in FIG. 1G. Themain difference is that the EMI ground pad structure 304 c of theembodiment shown in FIG. 4A at least extends to the interface betweenthe remained scribe region SC3 and the actual scribe region SC1. Forexample, the EMI ground pad structure 304 c extends across thepredetermined scribe region SC1 and reaches the peripheral contact padregion in the nearby die region. However, in another embodiment, the EMIground pad structure 304 c may extend to the actual scribe region SC1.

Then, as shown in FIG. 4B, the semiconductor substrate 300 is dicedalong the scribe line (i.e., the scribe region SC1) to form a pluralityof separate chip packages. Because the EMI ground pad structure 304 cextends across the scribe region, the EMI ground pad structure 304 c isexposed on a surface of the periphery of the remained scribe region SC3after the dicing process.

Then, the third conducting layer 330 d surrounding the periphery of theremained scribe region SC3 is formed. Because the first conducting layer330 a and the signal contact pad structure 304 a are separated from theperiphery of the remained scribe region SC3 by an interval, the formedthird conducting layer 330 d does not electrically contact with thefirst conducting layer 330 a and the signal contact pad structure 304 ato affect signal transmissions. In addition, after the third conductinglayer 330 d is formed, the third conducting layer 330 d may electricallycontact with the exposed conducting layer 330 c and the EMI ground padstructure 304 c. The third conducting layer 330 d surrounding the chippackage provides EMI shielding. In this embodiment, although the thirdconducting layer 330 d electrically contacts with both the conductinglayer 330 c and the EMI ground pad structure 304 c, the third conductinglayer 330 d may also only contact with the exposed EMI ground padstructure 304 c.

In addition, in the embodiments mentioned above, the EMI ground padstructure may include a plurality of metal layers (such as that shown inFIG. 1B) and directly contact with the second conducting layer throughone of the metal layers. For example, the EMI ground pad structure mayelectrically and/or directly contact with the second conducting layerthrough the bottom one of the metal layers. In addition, in anembodiment similar to that shown in FIG. 4, the EMI ground pad structuremay also include a plurality of metal layers and electrically and/ordirectly contact with the third conducting layer through one of themetal layers extending to the periphery of the remained scribe regionSC3.

Through the methods disclosed in the embodiments of the presentinvention, the conducting bumps electrically connected to the EMI groundpad structure may be placed on any position of the bottom of the chippackage, which may increase design freedom for the chip package. Inaddition, in some of the embodiments, the conducting layer or conductingpattern used for EMI shielding and the conducting layer or conductingpattern used for signal transmission may be simultaneously defined,which improves product throughput and reduces manufacturing time andcosts.

While the invention has been described by way of example and in terms ofthe preferred embodiments, it is to be understood that the invention isnot limited to the disclosed embodiments. To the contrary, it isintended to cover various modifications and similar arrangements (aswould be apparent to those skilled in the art). Therefore, the scope ofthe appended claims should be accorded the broadest interpretation so asto encompass all such modifications and similar arrangements.

What is claimed is:
 1. A method for forming a chip package, comprising:providing a semiconductor substrate having a plurality of die regionsand predetermined scribe regions, wherein each of the die regionscomprise at least a contact pad region and at least a device region, andthe predetermined scribe regions surround the die regions, wherein eachof predetermined scribe region comprises an actual scribe region, and aremained scribe region is between the predetermined scribe region andthe actual scribe region; forming a signal contact pad structure and anEMI ground pad structure on the contact pad region; forming a firstopening and a second opening through the substrate in the die region toexpose the signal contact pad structure and the EMI ground padstructure; forming a first conducting layer and a second conductinglayer in the first opening and the second opening to electricallycontact with the signal contact pad structure and the EMI ground padstructure, respectively, wherein the first conducting layer and thesignal contact pad structure are separated from a periphery of thepredetermined scribe region or the remained scribe region by aninterval, and the second conducting layer and/or a portion of the EMIpad structure at least extend(s) to an interface between the remainedscribe region and the actual scribe region; and dicing the semiconductorsubstrate along the actual scribe region to separate a plurality of chippackages, wherein the second conducting layer and/or a portion of theEMI ground pad structure extend(s) to a periphery of the remained scriberegion.
 2. The method for forming a chip package as claimed in claim 1,further comprising forming a third conducting layer to surround theperiphery of the remained scribe region and electrically connect to thesecond conducting layer and/or the EMI ground pad structure.
 3. Themethod for forming a chip package as claimed in claim 1, furthercomprising forming an insulating layer in the first opening and thesecond opening to separate the first conducting layer and the secondconducting layer.
 4. The method for forming a chip package as claimed inclaim 3, further comprising forming a recess in the predetermined scriberegion.
 5. The method for forming a chip package as claimed in claim 4,wherein the insulating layer is simultaneously formed in the firstopening, the second opening, and the recess.
 6. The method for forming achip package as claimed in claim 5, wherein the recess is formed bycutting the predetermined scribe region by a dicing blade to form aninclined outline.
 7. The method for forming a chip package as claimed inclaim 5, wherein the recess is formed by a dry etching process to form avertical outline.
 8. The method for forming a chip package as claimed inclaim 5, further comprising dicing the semiconductor substrate along thepredetermined scribe region and the recess to separate a plurality ofchip packages and leave the remained scribe region around a periphery ofeach of the chip packages, wherein the remained scribe region issurrounded by the insulating layer.
 9. The method for forming a chippackage as claimed in claim 8, further comprising forming a thirdconducting layer to surround the insulating layer around the peripheryof the remained scribe region and electrically connect to the secondconducting layer and/or the EMI ground pad structure.
 10. The method forforming a chip package as claimed in claim 4, wherein the semiconductorsubstrate comprises a first surface and an opposite second surface, thecontact pad regions are located on the first surface, and the firstopening, the second opening, and the recess are formed from the secondsurface.
 11. The method for forming a chip package as claimed in claim1, further comprising a package layer covering the semiconductorsubstrate.
 12. The method for forming a chip package as claimed in claim11, further comprising a spacer layer disposed between the package layerand the semiconductor substrate.
 13. The method for forming a chippackage as claimed in claim 12, further comprising forming a cavitybetween the package layer and the semiconductor substrate, wherein thecavity is surrounded by the spacer layer.
 14. The method for forming achip package as claimed in claim 11, wherein the package layer comprisesa silicon wafer and a transparent substrate.